- History of established coronary artery disease (CAD)as defined by coronary stenosis in one or more vessels greater than or equal to 70% by coronary angiography or CT angiogram OR abnormal stress test (at least medium-sized, moderate reversible defect) OR a presence of a CAD risk equivalent as defined by the National Cholesterol Education Panel (NCEP)III as: Framingham risk score ≥ 20%, diabetes, or peripheral arterial disease(4)